No. 9.A DISPUTE SETTLEDTHE STOMACH AGAIN. "Father, John and I don't agree about what you said of the bile last week ; where is it that it is mixed with the food, and what good does it do?" "I will get a picture and show you exactly how the food moves through the body. Here is tho lower end of the esophagus, which leads down from the mouth into tho stomach. When you swallow your food, it passes through this moist, limber pipe and falls into the stomach." 1, Stomach ; 2, Esophagus ; 3 nnd 4, Stomach ; 5 and 6, Duodenum ; 7, Jejunum ; 8, Ileum ; 9, Caecum ; 10, Vermiform Appendix ; 11,12, 13, 14, Colon; 15, Rectum. " As soon as any food enters the stomach, the gastric juice begins to be secreted, and is mixed with the food. It is found that unless the food is properly mixed with saliva, the digestion is very slow and imperfect, hence the importance of eating slowly." "Why so?" "The saliva is secreted by numerous gland in the mouth, called salivary glands, and they act, as a general rule, only while we are chewing our food. But while we are chewing, they are constantly pouring out this peculiar liquid, which is by no means pure water, but which has peculiar and powerful properties, acting upon the rood and preparing ic to be dissolved by the gastric juice. Therefore, the more slowly we eat, and the more thoroughly we masticate our food, the more perfectly is it mixed, with the saliva, and thus the more perfectly prepared for complete digestion by the stomach. There is no doubt that a great deal of dispepsia is caused by too rapid eating." "I have heard that said a good many times, but never understood it before." " After the food has been mixed with the gastric juice and churned from an hour and a half to five hours in the stomach, and has thus been converted into chyme, it is passed out into the duodenum ; here it is, marked 5 and 6, you see, in the cut. It is in the duodenum that the food is mixed with the bile. What the bile does is to change the chyme into chyle. The chyle is a milky liquid. The bile is secreted by tho liver. It flows first into a sac called the gall bladder, and then into the duodenum to mix with tho chyme and further dissolve it. Sometimes the duct which leads the bile into the duodenum gets choked up, and then the bile is absorbed by the blood and carried all over the system, imparting to the skin and eyes its own yellow color." "That is the cause of jaundice, is it?" "Sometimes. But as tho liver secretes about two quarts of bile a day, any slight derangement of it is sufficient to give the skin a sallow color. When the bile is thus turned from the duodenum into the blood, of course the digestion is interrupted, and thus indigestion and iaundice are very apt to accompany each other." "Did you not say something last week about the pancreatic j uice ? " "Yes ; it is by tho action of the bile and the pancreatic juice that tho chyme is converted into chyle. The pancreas is what tho butchers call ' sweet bread.' " "Where is it that the food which goes to nourish the system is taken out of the intestines?" "From the ileum, marked 8, you see, in tho cut. It is sucked up into little fine tubes which unite in a larger one that leads up by the side of the back bone and pours the food into a large vein in the left side of neck. The waste matter continues on up the colon, 11, across the body and down 12, 13 and 14, and out of the rectum, 15. " I understand it now by the aid of this cut, but last week I got no clear idea of it at all." " I think now you will remember tho course of the food, and next week, if nothing new prevents, we will come to the mode in which the fatty parts of the food are burned up and our bodies kept warm.”
This article was originally published with the title "Talk with the Boys"